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Aim of the study: Propolis is a natural product extensively used in food and beverages to improve health and to prevent diseases, showing immunomodulatory properties. The goal of this work was to evaluate the effect of propolis administration over a short-term to mice on Th1 (IL-2 and IFN-γ) and Th2 (IL-4 and IL-10) cytokines’ expression and production. Materials and methods: Propolis was administered for 3 days to mice by gavage, spleens were removed and RNA was extracted to assess cytokines’ expression by real-time PCR. Supernatants of spleen cell cultures were used for cytokines determination by ELISA. Results: Propolis administration to mice did not affect IL-2, IL-4 and IL-10 expression and production, while IFN-γ production was inhibited in the splenocyte cultures stimulated or not by Con A. Conclusions: Since IFN-γ is a pro-inflammatory cytokine, our data suggest that propolis administration over a short-term to mice may be associated with anti-inflammatory effects in vivo, and further assays could check propolis efficiency in inflammatory diseases. [Copyright &y& Elsevier]

Abstract: Aim of the study: Propolis has gained special attention due to its biological properties, however, little is known about its immunomodulatory effects in stress conditions. The purpose of this study was to investigate propolis effect on Th1/Th2 cytokines production by spleen cells of acutely stressed mice. Serum corticosterone concentration was determined as a stress indicator. Materials and methods: Male BALB/c mice were submitted to restraint stress and treated with propolis (200mg/kg) for 3 days. Supernatants of splenocytes cultures were assessed for Th1/Th2 cytokines determination. Results: Regarding Th1 cytokines production, no alterations were seen in IL-2 production; however, IFN-γ production was inhibited in stressed mice, even when treated with propolis. As to Th2 cytokines, IL-4 was inhibited in stressed mice, but normal levels were seen when these animals were treated with propolis. No significant differences were found in IL-10 production between the experimental groups. Stressed groups (treated or not with propolis) showed higher corticosterone concentrations in comparison to control group. Conclusions: Data suggest that propolis treatment was not able to counteract the stress-induced immunosuppressive effect on IFN-γ production; however, propolis showed an immunorestorative role, increasing IL-4 production in stressed mice, favoring humoral immune response during stress. Since the exact mechanisms of this natural product on immune system are still unclear, further studies are still required for a better comprehension of propolis use as a therapeutic alternative against the stress-induced negative effects that could lead to the development of various diseases. [Copyright &y& Elsevier]

In older adults, muscle strength (MS), a key component of sarcopenia, is essential to maintaining independence and physical capacity. The rate of MS decline typically accelerates during the menopausal transition. Although MS has been shown to increase with resistance training (RT), the response to training is quite heterogeneous. Thus, if contributing factors to RT non-responsiveness to MS gains are identified, it may be possible to develop more effective and personalized ways to improve MS or identify individuals who may benefit from RT interventions. This study assessed potential factors that may contribute to MS response heterogeneity in postmenopausal women: training frequency, serum FSH and estrogen levels, adiposity, inflammation marker, and insulin resistance. One hundred and thirteen individuals participated in a 16-week program of supervised RT (3 sets, 8–12 repetitions, and 2–3 times/week). A control group (CTL, n = 63 – no performed the RT) was used as the comparator arm. Body composition (skinfold) and blood samples (metabolic and inflammatory indicators and hormones) were measured at baseline. Knee extensor strength (1RM) was measured at baseline, 8 weeks, and 16 weeks. Only the RT group increased 1RM after 8 weeks (RT = 14 ± 12% vs. CTL = 6 ± 15%). Both groups increased 1RM after 16 weeks, with the RT group showing a greater increase than the CTL group (RT = 31 ± 23% vs CTL = 13 ± 25%). After 8 weeks of RT, 41 (36% of total) individuals were considered non-responders (based on control group responses) and 27 (24% of total) individuals after 16 weeks. At week 8, lower RT frequency (2 times/week vs. 3 times/week) was associated with higher odds of being non-responder (3 times, P = 0.048). At week 16, lower RT frequency (13 times, P = 0.009) and higher HOMA-IR (for every unit increase, odds increase by 40%, P = 0.022) were associated with higher odds of being non-responder. Higher QUICKI was associated with lower odds of being non-responder (for every unit increase, odds decrease by 16%, P = 0.039). Moreover, higher RT frequency (17 times, P = 0.028) and higher QUICKI (for every unit increase, odds increase by 41%, P = 0.017) were associated with higher odds of becoming a responder at week 16, being a non-responder at week 8. Heterogeneity in RT-induced MS responses is associated with training frequency and insulin resistance in postmenopausal women. • Response to resistance training (RT) is heterogeneous in postmenopausal women (PW). • RT non-response to muscle strength (MS) gains seem to be mitigated by higher RT frequency. • Insulin resistance seems to contribute to RT non-responsiveness to MS gains. • FSH, E 2 , CRP, adiposity seem not to contribute to RT non-response to MS gains. [ABSTRACT FROM AUTHOR]